1. Field of the Invention
The present invention relates to a composite-image parking-assistant system, particularly to a parking-assistant device, which integrates multiple bird's eye view images into a composite bird's eye view surrounding map and regulates the coverage of the vision field of the surrounding map according to the relative position of the vehicle and the parking space.
2. Description of the Related Art
Vehicles give modern people comfortable and fast transportation but also give modern people troublesome parking problems, especially in a crowded urban area where a parking place is usually only slightly larger than a vehicle. Therefore, a driver often uses the interior rear view mirror and the side rear view mirrors to learn the statuses of the rear, left and right sides of the vehicle.
However, a driver can only get a limited vision field from the conventional rear view mirror and is hard to always adjust the rear view mirror in driving to avoid blind spots. Thus, the driver usually has to lower the window glass and stretch out his head to detect the ambient status or slightly open the vehicle door to check whether there is a barrier in the side or the rear side of the vehicle. Sometimes, the driver may even ask the passengers to help observe the ambient status, or even the driver himself gets off the vehicle to examine the ambient status. These actions are all inconveniences for the driver.
To solve the above-mentioned problems, there was a rear view camera developed to capture the images of the parking space behind the vehicle, wherein the captured images are presented on the display inside the vehicle to help the driver reverse his vehicle into the parking space. Although the above-mentioned device can assists the driver in reversing his vehicle, the images captured by a single camera are hard to uncover all the blind spots around the vehicle. Thus, a system was proposed to overcome the above-mentioned problem, wherein a plurality of cameras replaces the single camera. The plurality of cameras captures a plurality of images around the vehicle. The images are then converted into a bird's eye view surrounding image. Although such a system can reveal most of the blind spots for the driver, the vision field of the bird's eye view surrounding image is usually too small—about only 2 meters. When the distance between the vehicle and the parking space exceeds 2 meters, the driver neither watch the whole parking space from the surrounding image presented on the display nor learns the space relationship between the vehicle and the parking space. If the driver should park his vehicle according to the surrounding image, a collision may occur.
Accordingly, the present invention proposes a composite-image parking-assistant system to overcome the conventional problems.